The present invention relates to a joining means between two pipes having retractable bearing members. This invention can be used for all couplings of pipes, no matter what the shape and form of the collars.
The coupling between two pipes is of great importance in certain applications. Thus, e.g. in a steam generator, the pipes are subject to thermal and mechanical stresses, which are partly transmitted to the joining means between two consecutive pipes. Moreover, said means must ensure a reliable, tight connection within the scope of the specifications imposed (temperature, pressure, etc.).
The conventionally used joining means comprise two collars joined at the end of each pipe. These collars have in each case a shoulder, between which is placed a gasket. The shape of the shoulders depends on the joints which they are to receive. Two flanges able to bear against these shoulders have holes traversed by tightening or gripping means (bolts, tie rods, etc.). The latter exert a force serving to bring together the two flanges and compress the joint.
In the cage of such means, the flanges must be fitted on the pipes prior to the fitting of the collars at the end of the pipe, because the internal diameter of these flanges is necessarily smaller than the external diameter of the collars. For the same reason, the dismantling of the flange makes it necessary to cut the collars, which is prejudicial to the reliability of the installation and also costly.